10.31.07
Evolving adenine
New Explanation For DNA Ingredient’s Emergence From Primordial Soup
By Brandon Keim October 31, 2007 | 9:20:46 AMCategories: Chemistry, Evolution
University of Georgia chemists have modeled a key DNA ingredient’s emergence from the primordial soup.
The ingredient, adenine, is one of four nucleotides that arose during the juvenile Earth’s 1.5 billion years of lifeless chemical volatility, eventually combining to form the molecular building blocks necessary for life as we know it.
Scientists have shown that adenine can be synthesized from large quantities of cyanide in volcano-like environments — something the early Earth had in abundance. But the molecular steps underlying this formation have remained a mystery.
Enter the University of Georgia chemists, who ran several years of quantum chemical computations on possible cyanide reactions and formulations. The result, published in the Proceedings of the National Academy of Sciences: under the right conditions, just five cyanide molecules can combine to form adenine.
So — good news for all you amateur origins-of-life-in-a-bottle enthusiasts out there! Now we just need to figure out thymine, cytosine and guanine.